CastingWords. I've been very happy with them for my purposes. They tend to even get various CamelCase product spellings and the like correct even if I forget to put them in the transcriber notes. I usually get the 6-day $1.50/min service partly because I need the turnaround and partly because, anecdotally, the quality also goes up a bit when you pay for the premium rates. I do maybe a couple dozen 20 minute podcasts a year so the costs are negligible.

Thanks for the plug, we love happy customers.

btw: We no longer use MTurk, we have our own crowd now.

Thanks. I'm dealing with hours of interviews per day.

Can you share about your use-case? I have a very similar transcription need--feel free to contact me at my email in profile